Machine for spray painting rotating and oscillating symmetrical hollow articles



Nov. 9, 1954 M. A. KNAPP MACHINE FOR SPRAY PAINTING ROTATING AND OSCILLATING SYMMETRICAL Filed March 12, 1951 HOLLOW ARTICLES 2 Sheets-Sheet 1 54 0m if L x6 1954 M. A. KNAPP 7 2,693,734

MACHINE FOR SPRAY PAINTING ROTATING AND OSCILLATING SYMMETRICAL Filed March 12, 1951 HOLLOW ARTICLES 2 Sheets-Sheet 2 khan/0r Will/12's Illa/R United States Patent Ofhee 2,693,784 Patented Nov. 9, 1954 MACHINE FOR SPRAY PAINTING ROTATING AND OSCILLATHJG SYMMETRICAL HOLLOW ARTICLES Maurice A. Knapp, Montreal, Quebec, Canada Application March 12, 1951, Serial No. 215,118

13 Claims. (Cl. 118321) This invention relates to improvements in painting machines, especially machines for spray painting lamp shades and other hollow articles presenting a continuous circumferential surface of vertical height such that the spray gun must be moved to direct a paint spray against the article from bottom to top thereof, and the primary object of the invention is to provide a machine for supporting and rotating articles to be painted and for so inclining the articles during painting that a uniform deposit of paint is ensured and application of paint to the interiors of the articles is prevented. A further object is to provide a machine so constructed that the articles to be painted form a shield between the spray gun and the machine, whereby deposition of paint on the machine is prevented. A still further object is to provide a painting machine capable of being easily and quickly adjusted to accommodate it to articles of a wide variety of shapes and sizes. An additional object is to provide a painting machine of simple, durable and inexpensive construction which may be operated with great ease and which will enable articles to be painted expeditiously. Various other objects and the advantages of the invention may be ascertained from the following description and the accompanying drawings.

Broadly speaking, the invention consists in a machine including a rotatable article carrier adapted to rotate an article relatively to a paint delivery point, preferably the nozzle of a paint spray gun, and to rock the article as it rotates in such wise that the axis of rotation of the article is moved from an inclination toward the paint delivery point to an inclination away from said point as the application of paint progresses from bottom to top of the article, or vice versa.

In greater detail, the invention consists in the features and combinations of features herein disclosed, together with all such modifications thereof and substitutions of equivalents therefor as are within the scope of the appended claims.

Heretofore, hollow articles such as lamp shades have been spray painted by hand work, the operator holding and turning the article with one hand and holding and operating a spray gun with the other hand, which method has the great disadvantages of low rate of output and high percentage of imperfect product, due to lack of uniformity in application of paint and to inadvertent application of paint to the interiors of the articles. Attempts to provide means to support and rotate the articles did not yield satisfactory results because of difficulty in properly supporting the articles and because the supporting means soon become coated with an accumulation of paint and required frequent cleaning to maintain it in serviceable condition. The present invention overcomes the aforesaid and other disadvantages by providing means to rotate and support articles and to change the inclination of the axis of article rotation as the painting progresses, whereby the support and the interiors of the articles are protected from deposit of paint thereon.

In the accompanying drawings which illustrate that embodiment of the invention now preferred but to the details of which the invention is not limited:

Fig. l is an elevation of my machine, partly in vertical section, as viewed from the front or working side.

Fig. 2 is an elevation of the machine looking toward the left hand end of Fig. 1.

Fig. 3 is a vertical cross-sectional view on the line 3-3 of Fig. 1.

Fig. 4 is a vertical cross-sectional view on the line 4-4 of Fig. 1

Fig. 5 is a vertical sectional view of the article support.

Fig. 6 is a horizontal cross-sectional view on the line 6-6 of Fig. 5.

Fig. 7 is a fragmentary front elevation illustrating one form decorating control.

Referring more particularly to the drawings, 11 desig nates a base vertically adjustable on feet 12, whereby the height of the machine may be adjusted to the convenience of the operator, the base constituting a housing for a motor 13, which may include a speed reduction gearing, if desired. A tubular column 14 rises from the base and has rigidly connected to its upper end, one end of a laterally extending arm 15. The arm 15 is preferably of inverted channel form and houses a shaft 16 mounted in ball bearings 17. The upper surface or'web of the arm may be semi-cylindrical in form and co-axial with the shaft, as shown best in Fig. 3. The shaft 16 is driven from the motor 13 through a shaft 18 housed in the column 14 and any suitable form of gearing indicated at 19. A brace 20 may be provided between the arm 15 and the column 14.

The shaft 16 projects beyond the free end of the arm 15 and carries a table 21 which serves as the base of an article support. This table 21 is mounted on the shaft by means of ball bearings 22. The free end of the arm 15 and the adjacent end of the table 21 are preferably formed with mutually engaging face plates 23, one of which carries a stop means 24 engaging in an arcuate slot 25 (Fig. 2) of the other plate, the curvature of which slot is concentric with the shaft. As will be seen, the table 21 is rotatable about the shaft and the stop and slot serve to limit the rotary movement of the table and the arrangement is preferably such that the table may be inclined forwardly and rearwardly from the horizontal through equal angles. Conveniently, the stop 24 may be a bolt carried by one face plate and passing through the slot of the other, having its head bearing against one of the face plates and its nut 26 bearing against the other face plate, whereby the plates may be clamped together to hold the table at any desired point in its arc of movement about the shaft. The table supports an article carrier designated, as a whole, by the numeral 27, which is rotatable about an axis disposed radially of the shaft 16 and operatively connected thereto by any suitable form of gearing indicated at 28. The gearings 19 and 28 may be the simple bevel gears illustrated or either or both of them may be worm gearing designed to eifect any neces 'sary speed reduction between the motor 13 and the article support.

The article carrier 27, which is shown in detail in Figs. 5 and 6, comprises a hollow core 29 of any desired cross-section, preferably cylindrical, having a depending stem 30 coaxial with the core, vertically slidable in a sleeve 31 and shouldered at 32 to rest on the upper end of the sleeve. The stem is irrevoluble in the sleeve and is preferably freely removable therefrom by upward movement. at 33 to rest on a ball thrust bearing 34 mounted in a carrier block 35 seated in the table 21 and the lower part of the sleeve depends through the carrier block which constitutes a circumferential bearing for the sleeve. The sleeve depends below the carrier block and carries one element of the gearing 28 irrevolubly connected thereto. An externally threaded hollow spindle 36 is revolubly mounted in the core 29, coaxially therewith, and may be formed with a circumferential series of depressions 37 for engagement by a spring pressed latch 38 mounted in the core, whereby the spindle is normally releasably held against rotation independently of the core. The spindle carries a nut 39 held irrevoluble with respect to the core by arms 40 projecting from the nut and through slots 41 in the core, parallel with the axis thereof. The thread of the spindle is preferably quite fast, for example a double thread as illustrated, so that only a few rotations of the spindle will be required to move the nut from end to end of the core. To facilitate movement of the nut, it may have ball bearing engagement 42 with the spindle threads. A rod 43 is slidably but irrevolubly mounted in the spindle 36,

The upper part of the sleeve is shouldered coaxial therewith, and is provided with any suitable -means 44 to facilitate manual rotation of the rod 43 and spindle 36. Any suitable means may be provided to releasably hold the rod at any desired vertical adjust- 'ment in the spindle, such as a spring'pressed latch 43 carried by the spindle and engageable in any one of a series of' depressions 43""11 the rod; The lower end of the core is provided with a series of stationary lugs 45 arranged in line with the slots 41. The nut arms 40 and the lugs 45 are spaced around the core and the spacing and number of them will depend on the shape .of the articles to be supported. For articles of circular, elliptical, square or octagonal cross-section, four arms and four lugs are preferred but for articles of other cross- ;sections, the number of arms and lugs may be more or less than four and the spacing may be unequal. Asso- 'ciated with'each arm 40 and its associated lug 45 is a system 46 of pivotally connected links constituting a structure commonly termed lazy tongs. Each arm 40 'is pivotally connected to the free end of an end link 47 at one side of the tongs and the related lug 45 is pivotally connected to the free end of an end link 48 at the other side of the tongs, whereby when the nut is moved down in theicore all the tongs are simultaneously extended, and vice versa. At the outer end of each linkage system, or tongs, which terminates at the level of the lugs 45, a foot plate 49 is pivotally mounted for oscillation in a vertical plane and is provided with means, such as a counterbalance weight 50, to hold it normally inclined toward the upper end of the core. The outer surface of each foot 49 is provided with a shoe 51 of -soft, elastic material, such as rubber sponge, which will have good frictional contact with the interior surface of an article to besupported and which will not damage the article. By rotating the rod 43, the tongs may be adjusted to the size of the articles to be supported. If desired, a scale 52 (Fig. 1) may be provided on the exterior of the core, adjacent a slot 41, whereby the position of the arm 40 relative to the scale indicates the extension of the tongs, for example in terms of inches of article diameter.

a The rod 43 is adjustable in the spindle 36 in order 'that the rod may provide a central support for the upper end of an article resting on the feet 49. For lamp shades, the support comprises a substantially spherical portion 53, which may serve as the rod turning means, of approximately the same diameter as an ordinary electric incandescent lamp, surmounted by a cylindrical portion of substantially the same diameter as the standard Edison screw base of an ordinary electric incandescent lamp, and an upstanding pin 55 of such diameter that it will 'easily enter the hub or washer of a lamp shade top frame adapted for impalement on the stud of a lamp. The table is provided with an arm '56, preferably of arcuate cross-section (see Fig. 3), overlying the arm 15 and extending beyond the column 14. The curvature of the table arm is preferably centered in the axis of the shaft 16 so that the arm may move over the cylindrically curved web of the arm 15, transversely thereof. If desired, the arm 56 may be provided near its free end with a supporting roller 57 running on the cylindrically curved surface of the arm 16. The free end of the arm 56 is formed with a forward extension 58 (Fig. 2) in which is mounted an axially vertical, rotatable lug 59 to which one end of a paint gun carrier 60 is pivotally connected for movement about a horizontal axis extending in the general longitudinal direction of the arm 56. The pivotal mounting of the lug 59 in the arm extension 58 and of the gun carrier in the lugs are of the adjustable friction type.

The gun carrier is preferably L-shaped and includes a telescopic vertical arm 61, the lower end of which is connected to the lug 59, and a horizontal arm 62 capable of extending approximately to the axis of the article carrier. Near its free end, the arm 62 carries a sleeve 63, slidable along the arm, to which is pivotally connected the upper end of a depending link 64. The lower end of the link is adapted to pivotally support a paint spraying gun, indicated at 65, with capacity to swing in a vertical plane. The telescopic arm 61 of the gun carrier may be adjusted to adjust the elevation of the horizontal arm according to the height of articles to be painted.

As the article carrier 27, table arm 56 and gun carrier 60 are all above the shaft 16 and the table which carries them is rotatable about the shaft 16, it will be obvious that the whole assembly will tend to swing forward or backward to the limits permitted by the stop 24. To control this tendency, the table 21 is provided with any suitable counterbalancing means. One such means comprises an arm 66 depending from the table and carrying a counterweight 67 adjustable on the arm toward and away from the shaft 16, according to the weight of articles to be mounted on the carrier and the position of the gun carrier 68 as determined by the size of the articles. The arm 66 is preferably inclined forwardly from the vertical axial plane of the shaft 16 sufficiently to give the table 21, article carrier 27, table arm 56 and gun carrier 60 a slight bias to forward swinging movement, as shown in Fig. 2.

Automatic starting and stopping of the motor 13 may be effected by locating the motor control switch 68 at the fixed end of the arm 15, beneath the arm 56, where the switch closing element 69 may be contacted by an actuator 70 on the under side of the arm 56, as best shown in Pig. 4. Because of the highly inflammable vapours of the paint solvent or diluent always present in the atmosphere during operation of the machine, it is necessary to use an enclosed switch, such as a mercury switch, and for the same reason it is preferred to use a completely enclosed motor.

Means are provided to enable the painting of wavy lines on an article and comprises, essentially, a tracking ring of suitably irregular profile which may be mounted on the machine when required, and a tracking roller co-operating with the ring and vertically movable thereby to impart relative vertical movement to the article and the spray gun. One such arrangement is shown in Fig. 5 and comprises a circular tracking ring 71 attachable to the table 21, concentric with respect to the stem 30, and having a waved or serrated upper tread surface. A tracking roller 72 is mounted on an arm 73 attached to the lower end of the core 29 and engages the tread surface of the tracking ring. As the article carrier rotates, the roller rides up and down on the ring and imparts vertical movement to the carrier and article thereon so that wavy lines may be painted on an article on the carrier by merely holding the spray gun, or a brush, stationary. The vertical movement of the carrier is permitted by the sliding engagement of the stem 30 in the sleeve 31. Another arrangement is shown in Fig. 7, in which a tracking ring 74 is secured to the lower end of the core 29 with its tread surface facing downwards and the tracking roller 75 is mounted on one end of a lever 75' fulcrumed on a lug 76 mounted on the arm 56, so that as the article support rotates the lever is oscillated in a vertical plane. The opposite end of the lever carries a link 77 adapted to be connected to the spray gun to move the same verticall during rotation of the article. The lug 76 may be located at any one of a series of stations 78 along the lever and along the arm 56. In either of the foregoing arrangements the tracking ring is easily applied and removed because of the easy removability of the article carrier from the table 21. It will be understood that whenpainting lines as above described, the table 21 should be clamped to the arm 15 to hold the carrier axis vertical. V

The operation of the machine is extremely simple and will be described in connection with painting lampshades. The elevation of the spray gun carrier is adjusted according to the height of the shade to be painted, so that the gun is supported at an elevation approximately midway between the bottom and the top of the shade when on the carrier 27. The lower end diameter of the shade, indicated at 79, having been ascertained, the knob 44 is rotated to rotate the rod 43 and spindle 36 and raise or lower thenut 39 to extend or contract the lazy tongs 46 until the shoes 51 will fit easily inside the bottom of the shade, the proper adjustment being ascertained by observing the position of .an arm 40 against the scale 52. Use of the scale eliminates trial and error and danger of damaging the shade. As shown, the lazy tongs have capacity for adjustment to accommodate shades up to the size indicated at 79 Fig. l. The latch 38 holds the spindle 36 against rotation independently of the core 29 during rotation of the carrier and thereby prevents the adjustments of the lazy tongs being altered by centrifugal force when the carrier is rotated. The rod 43 is vertically adjusted in the spindle according to the height of the shade, so that the center of the shade top frame may be engaged by an appropriate one of the elements 53, 54 or 55, according to the type of frame, and the shade held centered and against tipping on the carrier. The rod is held in its adjusted position by the latch 43. With proper adjustments, the rod 43 holds the shade at such elevation that it has only light frictional engagement with the shoes 51 of the lazy tongs and is prevented from descending on them to such extent as might damage the shade. The shade is mounted on the carrier by merely lowering it into position and is then held, as aforesaid, against being tipped on the carrier by the blast from the spray gun or by reason of the oscillation of the carrier. The mounting of the shade on the carrier is facilitated by the normal inclination of the feet 49 by the counterweights 50 and by the pivotal mounting of the feet which permits them to swing and adjust their inclinations to the inner surface of the shade. The normal inclination of the shoes is greater than the inclination of an ordinary shade wall, so that the shade first engages the lower end portions of the shoes and slides over them with foot tipping elfect in opposition to the action of the counterweights 50, which then urge the shoes against the shade with slight pressure suflicient only to afford a frictional driving contact between the carrier and the shade.

As already stated, the normal position of the article carrier is a forward inclination, as shown in full lines in Fig. 2. To paint a shade, the operator grasps the spray gun 65 with a slight lifting movement which is transmitted through the gun carrier 60, arm 56 and table 21 to rock the article carrier rearwardly to the position shown in broken lines in Fig. 2. At the commencement of this movement, the actuator 70 contacts and moves the switch closing member 69 so that the switch is closed and the motor started. The members 69 and 70 hold the switch closed until the article carrier returns to its forward position, whereupon the element 69 is released to permit closing of the switch and stopping of the motor. The carrier and the shade thereon are thus rotated during the inclination rearwardly and then forwardly, which is a normal painting cycle. At the commencement of the cycle, the operator holds the spray gun to direct the paint spray to the lower edge .of the shade, operator swings the gun upwardly to direct paint spray against upper parts of the shade, the movement is normally about a center in the operators wrist joint, so that the gun is moved bodily upward at-the same time its inclination is altered. The assembly of the gun carrier and article carrier is substantially in equilibrium with the counterweight 67 so that only very slight force is required to incline the article carrier. The aforesaid upward movement and tilting of the gun are continued until the paint spray is directed to the upper edge of the shade, as indicated by the line 81 of Fig. 2; at which time the carrier and shade thereon will have been tipped rearwardly to the position indicated in broken lines. When the rearward position of the shade is attained, the operator draws the gun forwardly and downwardly and at the same time inclines it downwardly so that a second coat of paint is applied to the shade. From the foregoing it will be readily understood that during the rearward tilting of the shade, the paint spray traces a helical path on the shade and that during the forward tilting the spray traces a second helical path but in the opposite direction to the first path, so that the paths intersect one another at a multitude of points, thus ensuring a uniform deposit of paint and avoiding the appearance or effect of lines of paint. While the normal operation is as just described, it will be understood that the relation of the rate of gun inclination to the rate of inclination of the shade is under the operators control so that he may vary the pitch of the helical paths traced on the shade by the paint spray and thus control, independently of the rate of paint discharge from the gun, the thickness of the paint deposit. As the table 21 is mounted on ball bearings on the shaft 16 and the assembly is counterbalanced, the small effort required to tilt the shade does not interfere with perfect control of the inclination of the gun. The counterweight 67 may be adjusted on the arm 66 according to the weight of the shade so that the operator may have the same facility of control when painting a large shade as when painting a small, light shade.

It will be observed that the paint sprays indicated by the lines 80 and 81 pass, respectively, under and over as indicated by the line 80 of Fig. 2. When the 16 the shade at such angles that it is impossible for paint to be inadvertently applied to the interior surface of the shade. It will also, be observed that the shade completely screens the table 21 and the shade carrier from the paint spray. The highest line of paint spray which will pass under the shade also passes well under the table 21 and arm 15 and the lowest line of paint spray which would pass over the shade also passes well over the top of the shade carrier.

While the machine has been illustrated and described as embodying a base 11 and column 14 to support the arm 15, it will be understood any other form of support may be substituted for these.

Having thus described my invention, I claim:

1. A painting machine comprising a support; an article carrier mounted for rotation about a normally vertical axis; means mounted on the support for oscillation about a horizontal axis and mounting the article carrier on the support; a spray gun carrier mounted on said article carrier mounting means and extending laterally of the axis of oscillation of the said mounting means with capacity to transmit movement thereto, whereby manual movement of a spray gun on said gun carrier to direct paint spray toward different elevations of an article on said article carrier is transmitted to and eifects oscillation of the article carrier; and means to rotate the article carrier during oscillation thereof.

2. A painting machine comprising a support; a horizontal shaft rotatably mounted in the support; an article carrier mounted for rotation about a normally vertical axis; means mounted for rotation on said shaft supporting the article carrier; a spray gun carrier mounted on said means and extending laterally of the axis of oscillation of said mounting means with capacity to transmit movement thereto, whereby manual movement of a spray gun on said gun carrier to direct paint spray toward different elevations of an article on said article carrier is transmitted to and effects oscillation of the article carrier; and driving connection between said shaft and said article carrier.

3. A painting machine comprising a support; a shaft rotatably mounted in said support; an article carrier mounted for rotation about an axis radial of said shaft; means for rotation on the shaft supporting the article carrier; a spray gun carrier mounted on said 'means on the same side of the shaft as said article carrier and extending laterally of the axis of oscillation of said mounting means with capacity to oscillate said article carrier supporting means; counterbalance means on the opposite side of the shaft from said article carrier and spray gun carrier, connected to said article carrier supporting means;

and driving connection between said shaft and said article carrier.

4. A painting machine comprising a support; a shaft mounted in said support and extending beyond one end of the support; a table mounted on the extending portion of said shaft for oscillation about the shaft; an article carrier mounted on said table for rotation about an axis radial of the shaft; driving connection between said shaft and said article carrier; a motor operatively connected to said shaft; motor control means including a switch mounted on one of said support and said table, and a switch actuating member mounted on the other of said support and said table; a spray gun carrier mounted on said table and extending laterally of the axis of oscillation of said mounting means with capacity to oscillate the table about the shaft, whereby movement of a spray gun on said gun carrier to direct paint spray toward different elevations of an article on said article carrier is transmitted to and effects oscillation of the table and article carrier and operation of the motor control switch.

5. A painting machine comprising a substantially horizontal support mounted at one end; a shaft rotatably mounted in the support and extending from the other end of the support; a table oscillatably mounted on the extending portion of the shaft; an article carrier rotatably mounted on the table, axially radial of the shaft; driving connection between the shaft and the article carrier; an extension from said table overlying said support; a spray gun carrier mounted on said extension at the end thereof remote from the article carrier and extending substantially to the article carrier, said gun carrier being adjustable vertically and radially of its point of support on the extension, according to the size of an article on the support, said gun carrier serving to transmit to the table and article carrier movement of the gun to direct paint spray to different elevations of an article on the carrier, thereby to oscillate the carrier.

6. A painting machine comprising a support; a shaft rotatably mounted in said support and extending beyond an end of the support; a table oscillatably mounted on the extending portion of said shaft; a sleeve rotatably mounted in said table axially radial of the shaft; driving connection between said shaft and said sleeve; an article carrier slidably but irrevolubly'mounted in said sleeve, including article engaging means adjustable to the size of an article to be painted; means to releasably lock said article engaging means against movement from an adjusted position by reason of centrifugal force resulting from rotation of the article carrier; and means to oscillate said article carrier and its supporting means as they rotate.

7. A painting machine comprising a support; a shaft rotatably mounted in said support and extending beyond an end of the support; a tableoscillatably mounted on the extending portion of said shaft; a member rotatably mounted in said table, axially radial of said shaft; driving connection between said shaft and said member; ad justable article engaging means extending radially from said member; means in said member to adjust said article engaging means in the radial direction of said member; and means to releasably hold the article engaging means against movement from an adjusted position by reason of centrifugal force resulting from rotation of said member.

8. A painting machine comprising a support; a shaft rotatably mounted in said support and extending beyond an end of the support; a table oscillatably mounted on the extending portion of said shaft; means to control oscillation of the table; a longitudinally slotted tubular member rotatably mounted in said table, axially radial of the shaft; driving connection between said shaft and said member; a threaded spindle rotatably mounted in said member; a nut on said spindle having arms extending through the member slots; lugs on said member; linkage systems of the lazy tongs type each pivotally connected at one end to a member lug and to a nut arm;

article engaging feet pivotally mounted at the outer ends 7 of said linkage systems; and a spring latch carried by said tubular member and engaging said spindle to hold the same against rotation under influence of centrifugal force acting on the linkage systems during rotation of said member.

9. Structure according to claim 8 including a rod slidable in said spindle and means at the upper end of said rod engageable with the upper end of an article supported by said feet to hold the article centered with respect to the tubular member and against being tilted on said feet by reason of oscillation of said tubular member and the blast from a paint spray gun.

10. A painting machine comprising a support; a shaft rotatably mounted in said support; extending beyond an end of the support; a table oscillatably mounted on the extending portion of the shaft; means to control oscillation of the table; a tubular member rotatably mounted in the table, axially radial of the shaft; driving connection between said shaft and said member; radially adjustable article engaging means projecting radially from said member and adapted to engage the lower end of an article to be painted; a further article engaging means slidably mounted in' said member in the axial direction thereof and adapted to engage the upper end of an article to hold the same concentric with respect to said member and against being tilted on said radially adjustable means by reason of oscillation of said tubular member and the blast from a paint spray gun.

11. A lampshade paintingmachine comprising a support; a lampshade carrier mounted on said support and rotatable about an oscillatable axis; means to rotate the carrier during oscillation thereof; said carrier including adjustable means to supportingly engage the interior surface of a lampshade at the bottom thereof and adjustable means to engage the shade at the center of its top to hold the shade centered on the carrier and against being tilted on said first mentioned shade supports by reason of oscillation of the carrier and the blast from a paint spray gun.

12. In a lampshade painting machine, a rotatable lampshade carrier including means adjustable radially of the carrier axis to frictionally engage the inner surface of a shade at a plurality of, points circumferentially spaced in the lower portion thereof and adjustable means to engage the center of the top frame of the shade, said last means including a plurality of differently shaped parts adapted to respectively engage different types of shade frames.

13. A lampshade painting machine comprising a lampshade support adjustable radially and axially according to the size of shade to be supported and adapted to engage a shade internally thereof; means to support said lampshade support and to rotate the same; and means to oscillate the shade support.

References Cited in the file of this patent UNITED STATES PATENTS Number Name 7 7 Date 181,338 Henry Aug. 22, 1876 460,670 Tschinkel 'Oct. 6, 1891 1,141,339 Hodgson June 1, 1915 1,656,977 Henry Jan. 24, 1928 2,358,258 Schweitzer Sept. 12, 1944 2,473,407 Adams June 14, 1949 

